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Seasonal And Spatial Variation In Primary Productivity In Boulder Basin, Lake Mead, Clark County, Nevada, Isamu Aoki May 1975

Seasonal And Spatial Variation In Primary Productivity In Boulder Basin, Lake Mead, Clark County, Nevada, Isamu Aoki

Publications (WR)

The 14C light and dark bottle technique for measurement of primary production was utilized as a means of assessing the amount of inorganic carbon being converted Into organic form by the photosynthesis of phytoplankton populations In the Boulder Basin of Lake Mead.

Spatial and time series changes of productivity levels observed at eight sampling locations within Boulder Basin Indicate that the Influence of treated municipal arts' industrial effluent flowing into Les Vegas Bay is contributing high levels of available nutrients at Las Vegas Wash Inlet to cause productivity to approximate those levels associated with polluted waters.

Productivity levels at …


Gas Exchange And Water Relations Of Two Alpine And Two Arctic Tundra Plant Species, Douglas Allan Johnson May 1975

Gas Exchange And Water Relations Of Two Alpine And Two Arctic Tundra Plant Species, Douglas Allan Johnson

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Although water stress is an important selective force in many environments, it is not commonly considered to be of particular importance in tundra areas. Even though large portions of tundra may have an abundance of water, other more exposed areas may become quite dry. This microsite variability with respect to moisture stress was reflected in soil water potential measurements obtained from an alpine tundra area on Niwot Ridge in Colorado. Even though soil water potentials were consistently above -5 bars in a relatively low lying Deschampsia meadow, soil water potentials from an exposed fellfield area were often as low as …


In Situ Nitrogen Fixation In Cold Desert Soil-Algae Crust In Northern Utah, Darwin Levoy Sorensen May 1975

In Situ Nitrogen Fixation In Cold Desert Soil-Algae Crust In Northern Utah, Darwin Levoy Sorensen

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Nitrogen fixation, as measured by the acetylene-ethylene assay, in the surface soils of southern Curlew Valley, Utah-Idaho was studied. The removal of nitrogen from the surface soil by precipitation runoff water was also studied, and the role of the soil-algae crust in preventing erosive loss of nitrogen was evaluated.

Nitrogen fixation during the study year was estimated to be less than 10 kg/ha. This level is probably sufficient to maintain steady-state on an annual basis in standing crop nitrogen in this environment.

Well structured, lichenous crusts had improved infiltration of precipitation and lowered erosive loss of nitrogen. Poorly structured and …


Structure Of Songs And Organization Of Singing In Fox Sparrows Breeding In Northern Utah And Southern Idaho, Dennis John Martin May 1975

Structure Of Songs And Organization Of Singing In Fox Sparrows Breeding In Northern Utah And Southern Idaho, Dennis John Martin

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Structure of songs and organization of singing in 133 Fox Sparrows Passerella iliaca were studied during 2 breeding seasons in 3 geographically separate populations in northern Utah and southern Idaho. The structure of songs was analyzed with the aid of an audiospectrograph. The organization of the singing of songs in 56 birds was analyzed by applying Markov chain analyses to the sequences of songs uttered.

Songs were composed of syllable-types, of which 49 were recognized. Syllable-types could occur singly or be serially repeated within songs, but they were never fractured so that only a portion of one would be in …


Regulation Of Rabbit Testicular Capsular Motility: The Interaction Of Prostaglandins, Acetylcholine And Sympathomimetic Agents, James L. Hargrove May 1975

Regulation Of Rabbit Testicular Capsular Motility: The Interaction Of Prostaglandins, Acetylcholine And Sympathomimetic Agents, James L. Hargrove

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The regulation of the contractility and intratesticular pressure of rabbit testes was studied. The effects of, and interactions among, prostaglandins (PGs) E1 and F2α testosterone, acetylcholine, epinephrine and norepinephrine were ascertained both in vitro and in vivo. All of these compounds, except for high concentrations of PGE1 and testosterone, stimulated the testicular capsule to contract. PGE1 at low concentrations potentiated the contractions produced by epinephrine and acetylcholine. Above 10-7M, PGE1 inhibited contractions caused by PGF2α epinephrine or acetylcholine. Testosterone inhibited contractions caused by PGF2α in vitro.

Preinjections of rabbits …


Respiratory Metabolism And Energy Requirements Of Embryo, Larval And Juvenile Mountain Whitefish, Prosopium Williamsoni, Pokkavil Karunakara Rajagopal May 1975

Respiratory Metabolism And Energy Requirements Of Embryo, Larval And Juvenile Mountain Whitefish, Prosopium Williamsoni, Pokkavil Karunakara Rajagopal

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The upper optimum temperature for embryonic development of mountain whitefish is 6 C, and for the post yolk sac stage is 9 to 12 C. The need to know effects on all stages in the life cycle in cases of thermal pollution is demonstrated. Abnormalities caused by thermal pollution in hatched larvae were agape jaws, coloboma or fissure of the eye, monophthalmia or the presence of only one eye, monomicrophthalmia or the presence of one small eye and one case of twinning. High mortalities of eggs occurred at 9 C and higher.

Study of the energy expenditure, by the dry …


Monoamine Oxidase As A Target Enzyme In Pineal And Testicular Tissue: Adrenal Cortical Steroids And Arginine Vasotocin, Randall James Merrill May 1975

Monoamine Oxidase As A Target Enzyme In Pineal And Testicular Tissue: Adrenal Cortical Steroids And Arginine Vasotocin, Randall James Merrill

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The purpose of the research was twofold: (a) To ascertain what effects the adrenal glucocorticoids and catecholamines have on pineal N-acetyltransferase and monoamine oxidase activity, and (b) to observe what effect arginine vasotocin (a pineal polypeptide) has on testicular monoamine oxidase activity.

Rat pineal N-acetyltransferase activity was numerically increased when rats were injected with cortisol. It was increased significantly when the animals were injected with cortisol plus norepinephrine. Adrenal demedullation significantly increased N-acetyltransferase activity in starved rats when compared with intact control animals. Moreover, bovine pineal monoamine oxidase activity was markedly inhibited in a dose-dependent manner when incubated in vitro …


The Effect Of Audible Sound On The Germination And Root Elongation Of Selected Seedlings, Micheal Dennis Walton Apr 1975

The Effect Of Audible Sound On The Germination And Root Elongation Of Selected Seedlings, Micheal Dennis Walton

Masters Theses

No abstract provided.


Skeletal Muscle Respiratory Capacity, Endurance, And Glycogen Utilization, Robert H. Fitts, F. W. Booth, W. W. Winder, J. O. Holloszy Apr 1975

Skeletal Muscle Respiratory Capacity, Endurance, And Glycogen Utilization, Robert H. Fitts, F. W. Booth, W. W. Winder, J. O. Holloszy

Biological Sciences Faculty Research and Publications

This study was undertaken to evaluate the relationship between physical performance capacity and the mitochondrial content of skeletal muscle. Four groups of rats were trained by means of treadmill running 5 days/wk for 13 wk. One group ran 10 min/day, a second group ran 30 min/day, a third group ran 60 min/day, and a fourth group ran 120 min/day. The magnitude of the exercise-induced adaptive increase in gastrocnemius muscle respiratory capacity varied over a twofold range in the four groups. There were significant correlations between the levels of three mitochondrial markers (cytochrome c, citrate synthase, respiratory capacity) in the …


Phosphorylated Β-Guanidinopropionate As A Substitute For Phosphocreatine In Rat Muscle, Coy D. Fitch, Max Jellinek, Robert H. Fitts, K. M. Baldwin, J. O. Holloszy Apr 1975

Phosphorylated Β-Guanidinopropionate As A Substitute For Phosphocreatine In Rat Muscle, Coy D. Fitch, Max Jellinek, Robert H. Fitts, K. M. Baldwin, J. O. Holloszy

Biological Sciences Faculty Research and Publications

To evaluate phosphorylated β-guanidinopropionate (β-GPAP) as a substitute for phosphocreatine (PC), hypoxic tibialis anterior muscles were stimulated to contract isometrically in situ until twitch tension fell to 25% of the peak value. Muscles from rats fed β-guanidinopropionic acid (β-GPA) failed to exhibit the staircase phenomenon, and they developed 28% less tension than control muscles. In control muscles lactate increased from 0.75 to 20.99, ADP increased from 0.89 to 1.20, ATP decreased from 5.09 to 2.73, and PC decreased from 15.78 to 1.52 μmol/g. In muscles from rats fed β-GPA, lactate increased from …


Eatonia No. 20, May 05, 1975, William L. Peters, Janice Peters Mar 1975

Eatonia No. 20, May 05, 1975, William L. Peters, Janice Peters

Eatonia

Eatonia was a newsletter established to facilitate communication among scientists working on a group of aquatic insects in the order Ephemeroptera, more commonly known as mayflies. The newsletter is named after Rev. Alfred E. Eaton who studied mayflies in England in the late 1800’s and is considered the “father” of the modern classification of mayflies.


The Surveillance Of Rodent Populations In East Africa In Relation To Plague Endemicity, S. Msangi Jan 1975

The Surveillance Of Rodent Populations In East Africa In Relation To Plague Endemicity, S. Msangi

Tanzania Journal of Science

Plague has been endemic in East Africa from very early times. The fact that the plague organism occurring in the area is mostly Pasteurella pestis var. antiqua which is said to have been associated with the Justinian pandemic of the 6th century A. D. would seem to support the contention that this endemicity was established during that pandemic. The maintenance of this endemicity has been made possible by the presence in the area of suitable rodent reservoirs, efficient flea vectors and favourable climatic and ecological conditions. The main reservoirs of plague in East Africa are Rattus rattus, Praomys natalensis and …


Electrochemical Machining (Ecm) With Alternating Current, S. J. Shine Jan 1975

Electrochemical Machining (Ecm) With Alternating Current, S. J. Shine

Tanzania Journal of Science

Electrochemistry has had several practical uses in industry for a long time; but one of the more recent applications is the machining of metals. Direct current ECM has been applied in industry for the last two decades. However, ECM with alternating current is still in the early stage of research and development. This paper shows that ECM with normal a.c supply is feasible and practicable if special tools are used. ECM with d.c. is first introduced to provide a better insight for the machining with a.c.


The Kunduchi Mangrove Basin, Alison Mccusker Jan 1975

The Kunduchi Mangrove Basin, Alison Mccusker

Tanzania Journal of Science

The pattern of tidal submergence and exposure in the Kunduchi mangrove basin is determined by contour mapping and by relating the contours to published tide predictions. Salinity of the creek effluent is measured at spring and neap tides in both wet and dry seasons. The vegetation of the basin, up to the highest high water level, is described briefly.


Eatonia Sup. 01, Jan. 05, 1975, William L. Peters, Janice Peters Jan 1975

Eatonia Sup. 01, Jan. 05, 1975, William L. Peters, Janice Peters

Eatonia

Eatonia was a newsletter established to facilitate communication among scientists working on a group of aquatic insects in the order Ephemeroptera, more commonly known as mayflies. The newsletter is named after Rev. Alfred E. Eaton who studied mayflies in England in the late 1800’s and is considered the “father” of the modern classification of mayflies.


Aquatic Ascomycetes From Lake Itasca, Minnesota, A. R. Cavaliere Jan 1975

Aquatic Ascomycetes From Lake Itasca, Minnesota, A. R. Cavaliere

Journal of the Minnesota Academy of Science

A preliminary report of the aquatic Ascomycetes of Lake Itasca, Minnesota. Included is an introduction, methods of harvesting and studying, a key, descriptions, and illustrations of 19 common ascomycetous fungi inhabiting the study area .


Pectis Humifusa New To The Flora Of The United States, David J. Keil Jan 1975

Pectis Humifusa New To The Flora Of The United States, David J. Keil

Biological Sciences

No abstract provided.


Ua66/6/3/1 Annual Newsletter, Kentucky Gamma, Alpha Epsilon Delta Jan 1975

Ua66/6/3/1 Annual Newsletter, Kentucky Gamma, Alpha Epsilon Delta

Student Organizations

Newsletter created by and about the Kentucky Gamma Chapter of Alpha Epsilon Delta premedical honor society sponsored by WKU Biology.


Chromosome Counts Of Compositae From The United States, Mexico, And Guatemala, David J. Keil, Tod F. Stuessy Jan 1975

Chromosome Counts Of Compositae From The United States, Mexico, And Guatemala, David J. Keil, Tod F. Stuessy

Biological Sciences

Chromosome numbers can be extremely useful in systematic studies, particularly for helping to reveal evolutionary relationships. For the past fifteen year numerous chromosome reports from plants have been published, especially in the Compositae, and these counts have been compiled in several major sources (Darlington & Wylie, 1955; Cave, 1958-65; Ornduff, 1967-69; Fedorov, 1969; Moore, 1970-72). However, a rapid glance through these references indicates not only that many species never have been counted, but also that many taxa are known only from a single plant in one population. In view of the common occurrence of euploid and aneuploid races in plants …


Aquatic Ascomycetes From Lake Itasca, Minnesota, A. R. Cavaliere Jan 1975

Aquatic Ascomycetes From Lake Itasca, Minnesota, A. R. Cavaliere

Biology Faculty Publications

A preliminary report of the aquatic Ascomycetes of Lake Isasca, Minnesota. Included is an introduction, methods of harvesting and studying, a key, description, and illustrations of 19 common ascomycetous fungi inhabiting the study area.


Developmental Study Of The Tumorous-Head Strain Of Drosophila Melanogaster, Suzanne Frances Dorgan Jan 1975

Developmental Study Of The Tumorous-Head Strain Of Drosophila Melanogaster, Suzanne Frances Dorgan

Retrospective Theses and Dissertations

No abstract provided.


The Evolution Of Alarm Calls: Altruism Or Manipulation?, Eric Charnov, John R. Krebs Jan 1975

The Evolution Of Alarm Calls: Altruism Or Manipulation?, Eric Charnov, John R. Krebs

Biology Faculty & Staff Publications

No abstract provided.


Actions Of Mammalian Gonadotrophins In Female Anolis Carolinensis (Green Anole) Within Selected Parameters Of Photoperiod And Temperature, Frank Loving Holt Jr. Jan 1975

Actions Of Mammalian Gonadotrophins In Female Anolis Carolinensis (Green Anole) Within Selected Parameters Of Photoperiod And Temperature, Frank Loving Holt Jr.

Master's Theses

The effects of either porcine FSHt equine LH, or both combined upon the pregametic a.nd gametic phases of the ovarian cycle of Anolis carolinensis {green anole)were investigated in animals maintained under one of three photothermal. regimens: 3 hours light at 15 C; 14 hours light at 15 C; or 14 hours light at 32 C.

Increases in pre-vitellogenic follicle diaaeter and ovarian weight were significantly greater at 32 C than at 15 c. A trend towards decreased numbers of atretic follicles with increased gonadotrophin dosage occurred in response to 14 hours light at 32 C. Gonadotrophin dosages which stimulated vitello­ …


Effects Of The Toxins Of Lophopodella Carteri (Ectoprocta), On Blood Lactate And Electrolytes Of Lepomis Macrochirus (Bluegill), Robert Fisher Dance Jan 1975

Effects Of The Toxins Of Lophopodella Carteri (Ectoprocta), On Blood Lactate And Electrolytes Of Lepomis Macrochirus (Bluegill), Robert Fisher Dance

Master's Theses

Specimens of bluegill (Lepomis macrochirus) were exposed to homogenates of Lophopodella carter, an ectoproct that contains substances toxic to some gilled vertebrates. The homogenates caused significant decreases in blood Na+ and Cl - and a significant increase in lactate. Potassium levels were unaffected. It is proposed that these changes in blood. properties were caused by damage to ion transport mechanisms of the gill epithelium.


Net Primary Production Of Spartina And Species Diversity Of Associated Macroinvertebrates Of A Semi-Impounded Salt Marsh, Larry Alan Chynoweth Jan 1975

Net Primary Production Of Spartina And Species Diversity Of Associated Macroinvertebrates Of A Semi-Impounded Salt Marsh, Larry Alan Chynoweth

Retrospective Theses and Dissertations

No abstract provided.


Donnan Potential Of Rabbit Skeletal Muscle Myofibrils I: Electrofluorochromometric Detection Of Potential, S. P. Scordilis, H. Tedeschi, C. Edwards Jan 1975

Donnan Potential Of Rabbit Skeletal Muscle Myofibrils I: Electrofluorochromometric Detection Of Potential, S. P. Scordilis, H. Tedeschi, C. Edwards

Biological Sciences: Faculty Publications

The fluorescence of the dye CC 6 [(3 hexyl 2 (3 hexyl 2 benzoxazolinylidene) 1 propenyl) benzoxazolium iodide] was shown to indicate Donnan potentials in rabbits skeletal muscle myofibrils. These results are in aggreement with previously published work in which the potentials were measured with microelectrodes on glycerol extracted muscle fibers. The magnitude of the Donnan potential of the myofibrils was shown to be dependent on the state (rigor or relaxed) of the system.


Numerical Taxonomy Of Anaerobic Bacteria Isolated From Ground Water Of A Sanitary Landfill, Kenneth J. Curry Jan 1975

Numerical Taxonomy Of Anaerobic Bacteria Isolated From Ground Water Of A Sanitary Landfill, Kenneth J. Curry

Retrospective Theses and Dissertations

Section I: Facultative and obligatory anaerobic bacteria were isolated from the ground water of a sanitary landfill characterized by sandy soil and a periodically high water table. Isolates were examined for 63 characteristics and subject to numerical analysis. Eight clusters were established and correlations with conventional taxonomy were made. The Bacteriodaceae were found to be the dominant group of organisms by the methods employed. The anaerobic population was observed to decrease as the period of seasonal rainfall ended. At the same time, gram positive anaerobes were largely replaced with gram negative ones. Leaching between sampling sites (wells) made correlations between …


Cyclic Patterns Of Central Florida Sooty Mold, Bobby Ray Pohlad Jan 1975

Cyclic Patterns Of Central Florida Sooty Mold, Bobby Ray Pohlad

Retrospective Theses and Dissertations

This study was conducted to record seasonal variations in the epiphyllous sooty mold colonies found on citrus leaves in two central Florida citrus groves, to determine basic patterns of fungal growth throughout the year and to determine whether these general patterns are correlated with regional climatological data. The results indicated general seasonal variations in the reproductive units of five of the fungi from the colony. In the study, correlations were seen between the two Ascomycetes, Treubiomyces pulcherrimus and Trichomerium didymopanacis. They were found fruiting most abundantly during the winter and spring. Reproductive units of two asexual sooty mold species (Podoxyphium …


A Serological Survey Of Greater Orlando Human, Canine, And Feline Populations For The Presence Of Antibodies To Toxoplasma Gondii, John Louis Weihe Jan 1975

A Serological Survey Of Greater Orlando Human, Canine, And Feline Populations For The Presence Of Antibodies To Toxoplasma Gondii, John Louis Weihe

Retrospective Theses and Dissertations

Toxoplasma gondii, the etiological agent of toxoplasmosis, was first discovered in Ctenodactylus gondi, an small North African rodent, by Nicolle and Manceaux in 1908. Later the same year Splendore observed the organism in a laboratory rabbit. Human infection was first reported by Janku in 1923. Since its discovery, many investigations have shown the organism to be truly unique in the protozoan world. There appears to be only one species and only one serotype. Serologic and microscopic studies reveal Toxoplasma to have a vast host range. At least one representative of virtually every mammalian species tested harbored the parasite or showed …


An Immunological Approach To The Study Of The Tumorous-Head Trait In Drosophila Melanogaster, Patricia Neuhaus Weihe Jan 1975

An Immunological Approach To The Study Of The Tumorous-Head Trait In Drosophila Melanogaster, Patricia Neuhaus Weihe

Retrospective Theses and Dissertations

No abstract provided.